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INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com
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ESSENTIALS OF A SMILE It involves the relationship between 3 primary components: Teeth Lip framework Gingival scaffolding
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Anatomy of the Smile The upper and lower lips frame the display zone of the smile. Within this framework, the components of the smile are the teeth and the gingival scaffold The soft-tissue determinants of the display zone are lip thickness, intercommissure width, interlabial gap, smile index (width/height), gingival architecture. Although the commissures of the lips form the lateral borders of the smile, the eye can perceive inner and outer commissures
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A PERFECT SMILE It is characterized by a medium lip line, an incisal line running against the upper border of the lower lip, an upper lip presenting an upward curvature. the mouth corners are symmetrically aligned to the papillary line and leave a proportional bilateral negative space.
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LIP LINES
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LIP LINE The lips define the esthetic zone and frame the smile The amount of tooth exposure on smile depends on a variety of factors like degree of contraction of the muscles of expression soft tissue level ,skeletal peculiarities, tooth shape and tooth wear. While low lip lines can sometimes be a cover for poor dentistry the high lip line is more of an esthetic challenge to handle. The ideal lip line is when smiling the lip elevates to the interdental gingival margin
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NEGATIVE SPACE It is the dark space that appears between the jaws when laughing and smiling. It promotes the dental composition by providing contrast. These lateral spaces are due to the difference in width between the maxillary arch and the breadth of the smile.
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The application of the divine proportion to dentistry was attributed to Lombardi and then developed by Levin.
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Using calipers that open at a constant divine proportion between the larger and smaller parts, Levin observed that in esthetically pleasing dentitions viewed from the front the width of the central incisors in the golden proportion to the lateral incisor which is in golden proportion to the anterior part of the canine. He also demonstrated that the width of the negative space is in golden proportion to one half of the width of the anterior segment.
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From these observations he developed a grid to test the validity of this statement, in the grid the incisors are quoted within a large range of width. The use of this grid helps the dentist determine what is esthetically wrong with the anterior proportional dentition. www.indiandentalacademy.com
The buccal corridor is said to be in golden proportion to the anterior smiling segment. Adequate restoration of this space permits characterization of the smile. It is a key factor in the harmony of a smile.
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SMILE SYMMETRY: It refers to the identical placement of the corners of the mouth in the vertical plane of the face. A coincidence between the commissural line and the line drawn from one cuspid to another is another attribute of an esthetic smile. there must be parallelism between the commissural line, the occlusal line , interpupillary line and the hypothetical gingival line passing through the zenith of the teeth.
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AXIAL ALIGNMENT It is generally accepted that the anterior dentition when viewed from the front should possess an inclination to the mesial that becomes more pronounced when proceeding from central incisor to the canine. Posterior teeth too when viewed from the premolar to the first or second molar show an increasing axial inclination to the mesial.
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GRADATION Also known as front back progression. When one similar structures are aligned one after another they undergo a progressive visual reduction of size from the nearest to the farthest.
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This phenomenon of front back progression is used to give an illusion of depth to the smile. The buccal corridor helps in achieving this gradation effect. It reduces perception of details at the back but in turn enhances depth. This progression is also determined by arch form .
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SQUARE DENTAL ARCH
OVOID DENTAL ARCH
TAPERED DENTAL ARCH
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CONTACT POINTS 
In the anterior view the contact points are situated in a position that goes from incisal to cervical from the incisors to the canines and an imaginary line joining these contact points is a curve emphasizing the curve of the lower lip.
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GINGIVAL CONTOURS: In healthy individuals the gingival tissues blend into the tooth embrasure which is totally filled and is esthetically ideal. The development of an unaesthetic black triangle can appear with recession or due to abnormal tooth morphology and contact.
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Health and integrity are not esthetically enough. An irregular gingival margin detracts from the inherent health it may possess. It is desirable to establish harmony and continuity of the gingival form of the free gingival margin. The gingival margins of the two centrals must mirror each other and the level of gingival attachment of the laterals incisor must be more incisal yet symmetrical to the other lateral incisor. The cuspid’s marginal gingival must be at the same level as that of the central incisor and the premolar somewhat more coronal. www.indiandentalacademy.com
The most apical point of gingival tissue is located distal to the long axis of the central incisor and canine. In the mandibular incisors and the maxillary lateral incisor the zenith is located along the tooth axis
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The gingival height in class II div 2 incisors: The horizontal level of the gingival margin of the lateral incisor is located at a higher level than the centrals and also tends to overlap the centrals. Iin a Class I occlusion the gingival margin is symmetric parallel and horizontal arrangement is esthetically pleasing.The margins of the two central incisors mirror each other, the lateral gingival margins are lower and symmetric and the canines are at the same/slightly higher level as the central incisors. www.indiandentalacademy.com
Contemporary orthodontic evaluation attempts to evaluate and examine static and dynamically the anatomic and physiologic jaw tooth relationships. Not only is the problem oriented treatment planning being followed, the orthodontist as an architect of the smile needs to identify and quantify the elements of the smile that needs correction, enhancement and improvement as well as identifying the positive elements of the smile that must be saved. The orthodontist of today must evaluate patients not only in the profile but also vertically and transversely as well as the fourth dimension of time. Hence the emphasis on orthodontists to understand the changes that occur with time.
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THE TIME FACTOR: Growth and maturation as well as aging of the perioral soft tissues have a profound effect on the appearance of the resting and smiling presentations.
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Changes in lip length and thickness associated with growth Both upper and lower lips grows more than the skeletal lower face in children . In both absolute and proportional terms the lower lip grew more than the upper lip. (Subtelny) The upper lip showed rapid increase in length from age 1-3. The rate of growth was then reduced from age 3-6 when again an upswing occurred till the age of 15. The growth curve for the upper lip was similar to the growth curve for the general body growth curve. (Vig and Cohen ) www.indiandentalacademy.com
The clinical relevance of this study •Most children with lip incompetence at age 6 experience self correction by age 16. •Lip competence is important not only in terms of esthetics but also stability of overjet correction. •In this age group 6-8, when it looks as though that the incompetancy is due to short lips whereas it is just incomplete soft tissue growth.
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Mamandras •that males between the ages of 7-17 had a greater increase in lip length than females in the same period. •The males experienced little more than 2mm in the vertical growth of the upper lip whereas in females it was less than an mm . Genecov •In females vertical lip growth was complete by 14 whereas by males it leveled off at 18. •Mandibular lip length increased till 16 in females whereas in males it was not completed at 18. www.indiandentalacademy.com
LIP THICKNESS DURING GROWTH AND MATURITY: In Subtelny’s study the upper lip attained a greater thickness in the vermillion region than over point A. This increase in thickness at the vermillion border was approximately equal to the increase in length of the lip. In both males and females the upper lip increased in thickness from ages 114. After the age of 14 the lips continued to become thicker in males but not in females. Similarly in the lower lip the gain in thickness was greater at vermillion border than at Pogonion or point B Lip thickness increase for males form ages 1-18 was around 7mm while for females it was around 6mm.
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Mamandras in his study of lip thickness found that the female lip thickened till the age of 14 after which it remained the same till the age of 18 beyond which it showed thinning. Males attained maximum lip thickness by age of 16 after which they too showed thinning. Horizontal thickness of both sexes completed by age15.
Nanda slightly differed from Mamandras. He found that lip thickness increased uniformly from age 7-18, females attained full lip thickness by age 13 with slight thinning starting then.In males however the thickness continued till the age of 18.
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Clinical applications of this data: The differential in the two sexes with respect to lip thickness implies that the treatment result of extraction therapy of the facial profile will be more noticeable in female than male patients. Because female lips do not thicken with age , any extraction plan for females with straight to convex profiles should be cautiously considered. Lip fullness in relation to the nose which will continue to grow should also be noted.
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NASAL GROWTH AND ITS CONTRIBUTION TO PROFILE Class II patients exhibited a more pronounced elevation of the bridge of the nose than class I. the dorsum of the class II cases also shoed an increased general convexity. Class I tended to have straighter noses. Females did not show such a spurt in growth like males but had a more steady increase in nose growth. Manera and Subtelny Subtelny first documented the downward and forward growth of the nose with maturity.The vertical dimension of the nose experiences more growth than the anterior posterior projection in both males and females. There was a spurt in male’s nasal growth from 10-16 with a peak around 13-14 years www.indiandentalacademy.com
This was of importance because an orthodontist treating a class II girl aged 12 could expect only minimal increases in nasal projection over the next few years.
However in a male of a similar age any treatment that causes upper lip retraction in combination with several mm of nose growth might produce a less than optimal final relationship between the lips and nose.
The increased prominence of the nasal hump in boys coincides with pubertal spurt and nasal projection in girls peaks between 9-10. www.indiandentalacademy.com
THE CHIN Genecov’s study documented that soft tissue chin thickness in females from age 7-9 was greater than males .Females only had a 1.6mm increase upto age 18 whereas the males had a 2.4mm increase in soft tissue drape over the chin. As a result both sexes had a similar soft tissue thickness at age 17. In Nanda’s study, the soft issue thickness over the chin. symphysis thickness and the length of the mandibular corpus, all 3 distances increased with age, the males showing the largest increments. Till 7 years the size of the mandibular corpus was the same for both sexes. and the curves progressed parallel to each other till the age of 15 when the male sample had larger increases than the female. Increased chin projection seen in the males is due to the mandibular growth than the increase in soft tissue chin thickness. www.indiandentalacademy.com
THE MATURE FACE The reasons why the orthodontist should understand about the aging of the face is because •the orthodontist when treating an adolescent is making decisions about how the individual will look for the rest of his life. •the increasing demand for adult orthodontics and orthognathic surgery increases the need to understand the facial aging process. •an increase in the complexity of treatment plans and the expectations of the patients is also a factor. •The age usually having orthognathic surgery includes 28-35 and they soon move into middle age when aging becomes most apparent. The blame may be easily placed on orthodontics by the patient.
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The general soft tissue changes in males between the ages of 18-42 included the following finding: The profile straightened, the lips became more retrusive The nose increased in size in all dimensions. There was increased soft tissue thickness at the Pogonion. There was decreased upper lip thickness and slightly increased lower lip thickness In females: The profile did not become straighter and the lips did not become more protrusive The nose increased in size in all dimensions. There was decreased soft tissue thickness at the Pogonion. There was upper lip thickness and slightly increased lower lip thickness
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THE AGING FACE: Behrents In young adulthood, 17-41 subjects tended to be specific to their craniofacial patterns. In other words ClassII subjects grew as class II while class III grew as class III. In later adulthood vertical dimensional changes were common to all subjects. they became less protrusive with greater facial height increase. the males exhibited counterclockwise rotation of the mandible. The percentages of change in the females were less and growth tended to be more vertical.
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Nasal changesThere was an increase in nasal projection and the nasal tip moved more inferiorly. Lip thickness: the lips became less prominent and were located more inferiorly. that is the upper lip tended to rotate down and back from the base of the nose. This would naturally imply that less maxillary incisor would be exposed at rest and smile which is corroborated clinically. Nasolabial changes:With the decrease in lip prominence and the lowering of the tip the nasolabial angle became more acute. Dental changes:In females the maxillary incisors became more upright and the lower incisors became more proclined.the lower molar uprighted in males and moved forward in females. The upper molar tilted forward in the male but uprighted in the females.
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FEATURES ASSOCIATED WITH AGING: Lower part of the face appears to lengthen the interlabial line descends , the number of vertical fibers in the upper lip reduces. the philtral columns become less prominent and the vermillion becomes a straight line. Jowling and increased nasolabial folds are seen. the M and W shapes of the lips may become straight. the comissures droop giving the look of a frown.
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beauty is not the norm Proffit states that the basis of the practice of orthodontics is changing rapidly as a result of 3 major influences: the biologic revolution, the recognition that the facial soft tissues are the primary focus of orthodontic treatment, and the growing reliance on evidence-based rather than opinion-based orthodontic research. Treatment decision making must be determined by what’s esthetically appealing than what the cephalometric norms may be. www.indiandentalacademy.com
The dynamics of soft tissues involved are twofold:
Examination of the smile in animation and repose which includes parameters such as gingival display, crown length and lip animation and other such attributes.
The second factor is that the patient changes with age, the impact of hard and soft tissue aging cannot be minimized.
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RECORDS IN THE TREATMENT OF THE SMILE Orthodontic records are of three types: Static records, dynamic records , direct biometric measurements. Visualization and quantification of the dynamics of the smile is a two stage process: The critical first stage is clinical examination with the evaluation of the lip tooth relationship both statically and dynamically. Record taking is the second step with digital photography, videography, radiography and models. These are taken from a frontal and oblique direction to record a three dimensional description of the smile characteristics. www.indiandentalacademy.com
The records therefore needed for smile visualization and quantification are 1)static the additional photographic images needed are: profile and oblique smile and oblique and frontal smile close ups. 2) dynamic
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WHY DIGITAL VIDEOGRAPHY ?
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Capturing patient smile images with conventional 35mm photography has some major drawbacks. Difficult to standardize photographs Difference in appearance of the smile arc in intraoral and extraoral views When several consecutive smile photographs are taken at the orthodontic records visit, the clinician will often note variations in the smile. In children, this phenomenon is most likely due to relatively late maturation of the social smile. Standardized digital videography allows the clinician to capture a patient’s speech, oral and pharyngeal function, and smile at the same time.
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Digital technology allows the anterior tooth display to be recorded at 30 frames per sec.normally 5 secs of recording is done.
The videos are recorded in a standardized fashion with the camera at a fixed distance from the subject. One segment is taken in a frontal direction and another in a oblique direction.
These clips are taken before and after treatment and help to assess the changes in smile characteristics bought about by orthodontic treatment.
The patient’s head is placed in a cephalometric holder and asked to say, “Chelsea eats cheesecake in the Chesapeake” and then to smile. The video clip is reviewed and the frame that represents the patient’ natural unstrained social smile is selected. www.indiandentalacademy.com
DIGITAL RECORDING OF THE SMILE
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Digital radiography also helps to ascertain the patient’s smile style: According to Rubin there are three smile styles: Commissure smile/ Mona Lisa smile: Cuspid smile Complex smile
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Smile Analysis first the clinician should assess tongue posture and lip function, particularly during speech. Immature oral and pharyngeal function with unfavorable tongue posture can easily be detected. The frame that best represents the patient’s social smile is selected, saved as a JPEG file. The smile image is then opened in a program called SmileMesh, which measures 15 attributes of the smile
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This methodology was first used manually by Hulsey and later modified and computerized by Ackerman Its most significant advantage is that the orthodontist can quantify such aspects of the smile as maxillary incisor display, upper lip drape, buccal corridor ratio, maxillary midline offset, interlabial gap, and intercommissure width in the frontal plane. The flaw in traditional smile analysis has been that many of the vertical and anteroposterior calculations related to anterior tooth display are made from the tracing of the lateral cephalogram, which is taken in repose. As a result, incisor position has been determined from a static rather than a dynamic record. www.indiandentalacademy.com
Direct Biometric measurements:
1. 2. 3. 4. 5. 6.
Philtrum and Commissure height Interlabial gap Incisor show at smile& rest Crown height Gingival displacement Smile arc
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Smiles can be either posed or spontaneous. The posed smile or social smile is voluntary and need not be elicited or accompanied by emotion. A posed smile is static in the sense that it can be sustained. The lip animation is fairly reproducible, In treating a social smile represents a repeatable smile, though it can mature and might not be consistent over time with some patients.
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The unposed smile is involuntary and is induced by joy or mirth. It is dynamic in the sense that it bursts forth but is not sustained. An unposed smile is natural in that it expresses authentic human emotion. Lip elevation in the unposed smile is often more animated, as www.indiandentalacademy.com
seen in the laughing
The social smile is chosen to undergo examination in 4 dimensions: Frontal. Sagittal, oblique and time related.
Frontal.
Sagittal
Smile Index
Over jet
Vertical / Transverse Smile Characteristics
Incisal Angulations Transverse effect
Oblique Palatal Plane Orientation
Smile Arc
Time Growth Maturation Aging
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FRONTAL DIMENSION: Smile index: It describes the area framed by the vermillion border during the social smile. It is determined by dividing the inter commissural width by the inter-labial gap during smile. It can be used to compare two patients or one patient at two different times. A small smile index would imply a gummy smile.
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Vertical dimensions
Vertical parameters: •Incisal display •Gingival display •Relationship between the incisal margins of the upper incisors and the lower lip •Gingival margin with the upper lip
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CAUSES OF LIP INCOMPETANCE Vertical maxillary excess with excessive lower facial height Maxillary impaction via Le Fort I osteotomy Excessive lower facial height due to excessive chin height Vertical genioplasty Short philtrum V-Y cheiloplasty Excessive overjet orthodontics
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EXCESSIVE UPPER INCISOR SHOW AT REST AND ON SMILE The reasons could include both hard and soft tissue factors Short philtrum V-Y cheiloplasty Vertical maxillary excess Maxillary impaction via Le Fort I osteotomy Long incisor crown height Crown height reduction Hyper-mobile smile Cartilage or spacer technique Kamer technique De-torqued incisors Orthodontic incisor torque www.indiandentalacademy.com
Long philtrum Not often seen, no procedure Vertical maxillary deficiency Maxillary downgraft Short incisor crown height Gingival procedures like gingivectomy Crown lengthening Flared maxillary incisors Orthodontic retraction and up righting Diminished anterior dentoalveolar eruption secondary to chronic digit habit Orthodontic leveling Surgical correction Inadequate curtain on smile www.indiandentalacademy.com
MAXILLARY INCISOR DISPLAY The amount of the incisor show at rest is a critical esthetic parameter because a sign of aging is decreased show of the maxillary incisor.
According to VIG and BRUNDEL Tooth exposure at rest (in mm) Male 1.91 mm Female 3.40 mm
mand incisor- 1.23 mand incisor- .49
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Tooth exposure by race Race max CI White 2.43 Black 1.57 Asian 1.86
Tooth exposure by age Age max CI Upto 29 3.37 30-39 1.58 40-49 .95 50-59 .46 60+ -.04
mand CI .51 .8 1.96 2.44 2.95
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mand CI .98 1.42 1.58
CROWN LENGTH The vertical height of the maxillary central incisors is between 9 to 12 mm. The age of the patient plays a role because primary incisors measures only 4-5mm vertically. Incomplete eruption of the crowns could also present as short clinical crowns Thick fibrotic gingival tends to migrate slowly so this must be ruled out. In an adolescent the periodontal contribution to the gumminess of a smile must be evaluated. There may be a delay in the apical migration of the gingival tissues. The treatment also varies depending on whether the lack of clinical crown length is due to gingival encroachment or loss of tooth structure incisally. www.indiandentalacademy.com
SMILE CURTAIN A smile curtain is the amount of mobility and elevation of the upper lip. Patients with an excessive smile curtain simply have and greater than average range of smile activity than normal. therefore to attempt to correct a hyper mobile smile through impaction would adversely affect the incisor lip relation at rest adversely and would age the patient. The upper lip would also thin and the curvature of the resting lip would worsen. Treatment of the hyper mobile smile: Smile immobilization can be done by inserting a spacer of cartilage or silicone between the septum and the maxillary alveolar mucosa. The Kamer technique is simpler than the spacer technique and produces the same result. Kamer in his technique excised a horizontal strip of labial mucosa and attached an inferiorly based mucosal flap from the opposing alveolar mucosa which effectively decreases the height of the gingival www.indiandentalacademy.com
ALTERED PASSIVE ERUPTION: Aberration in normal development where a large portion of the anatomic crown remains covered by gingiva. Unaesthetic for two reasons: The normal scalloping is absent, teeth are short and squat. A potentially medium lip line is converted to a high lip line. Types of altered passive eruption: type I : there is an increased amount of gingiva from the margin to the alveolar mucosa type II: there is normal amount of attached gingiva from Free gingival margin to the alveolar mucosa. Type IA: 1mm present between Cemento enamel junction and osseous level ( treated by gingivectomy) Type 2A : osseous level close to the Cemento enamel junction (treated by a flap and osseous resection) www.indiandentalacademy.com
METHODS OF DEVELOPING GINGIVAL HARMONY: SURGICAL Additive gingival techniques Resective gingival techniques
ORTHODONTICS extrusion intrusion
The greatest advantage of orthodontic tooth movement is the movement of the attachment apparatus along with the tooth. Therefore in health while extruding teeth orthodontically the gingival margin moves the same distance and in the same direction as the incisal edge.Concomittantly so will the osseous level. Therefore intrusion or extrusion can be used from an esthetic perspective to develop gingival margin symmetry without periodontal surgery.
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TREATMENT OF A COMBINATION CASE OF VME AND ALTERED PASSIVE ERUPTION: 1st one should develop the normal silhouette form of the teeth by removing the altered passive eruption component next orthognathic surgery – impaction limited by the resting lip to incisor relation.( 2mm show esthetically desirable) Finally after surgery according to patient’s desire, further gingival display can be reduced by a flap and osseous resection.
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The smile arc is defined as the relationship of the curvature of the incisal edges of the maxillary incisors and canines to the curvature of the lower lip in the posed smile. The ideal smile arc has the maxillary incisal edge curvature parallel to the curvature of the lower lip. The smile arc is more curved for women than men.
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Modification of the smile arc: Growth modification in pre adolescents to treat the occlusal plane Late adolescents and adults orthognathic surgery is indicated to treat the occlusal plane Bracket placement to enhance/ maintain the smile arc Multi disciplinary approach: periodontal surgery, cosmetic laminates and esthetic bonding as well as enamel odontoplasty to reshape incisal edges
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Smile arc flattening during orthodontic treatment can occur in several ways.
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Normal orthodontic alignment of the maxillary and mandibular arches may result in a loss of the curvature of the maxillary incisors relative to the lower lip curvature A set formula for bracket placement based on tooth measurements, is not appropriate for maximum esthetics Bracket placement may lead to superior repositioning of the incisal edges relative to the posterior buccal segment heights. In patients in whom excessive gingival display on smile is noted, maxillary incisor intrusion may improve the gingival display on smile. However, if the smile arc relationship has not been noted and evaluated, unwanted flattening of the smile arc may result. Maxillary intrusion arches or maxillary archwires with accentuated curve could result in a flattening of the smile arc www.indiandentalacademy.com
Transverse parameters: Arch form Buccal corridor Transverse cant Broadening out a narrow arch can have two disadvantages, first the buccal corridors could be obliterated, and second the broader arch form could flatten the smile arch. Smile asymmetry Could be due to asymmetric smile curtain Differential eruption of anterior teeth Skeletal asymmetry
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Arch form: The patient’s archform—and particularly the configuration of the anterior segment—will greatly influence the degree of curvature of the smile arc. The broader the archform, the less curvature of the anterior segment and the greater the likelihood of a flat smile arc.
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OBLIQUE DIMENSIONS: This view shows smile characteristics not seen with the frontal view, especially relevant in sagittal skeletal discrepancies. In an esthetically pleasing smile the cant of the occlusal plane is consonant with the curvature of the lower lip. The smile arc as defined from the oblique direction: It is the relation of the incisal edges of the incisors canines’ premolars and molars to the curvature of the lower lip during a posed social smile. Ideally the curvature of the incisal edges is consonant with the lower lip and is parallel. a non consonant smile arc describes a flat incisal curvature.
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SAGITTAL DIMENSION The two characteristic of the smile that are best viewed in this view is the overjet and incisor angulations . *Excessive overjet is not perceived in the frontal dimension as well as it is in the sagittal dimension. In class II and III’s the frontal smile is usually esthetic. *Posterior positioning of the maxilla in the sagittal plane can increase the buccal corridors in the frontal plane. *Incisor inclination also plays a role in vertical incisor display. Proclined incisors tend to reduce incisal show while retroclined incisors increase show. www.indiandentalacademy.com
SMILE ANALYSIS The diagnostic part of smile analysis begins with the creation of a problem list. The first set of records analyzed is the extraoral photo gallery Consideration should be given to the vertical and lateral attributes of the smile as well as to the cant of the transverse occlusal plane Next, the cant of the maxillary occlusal plane relative to Frankfort horizontal should be assessed visually on the lateral cephalogram and measured on the tracing. Vertical and anteroposterior skeletal and dental relationships are noted. Panoramic and supplemental intraoral radiographs are also analyzed. Finally, the plaster study casts are evaluated for static occlusal relationships and tooth-size discrepancies.
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Clinical Implications for Low and Average Smile Types In most deep overbite cases, intrusion will tend to hide the maxillary anterior teeth behind the upper lip in normal conversation. Such a mistake can go undetected by the orthodontist unless the patient's tooth display and smile are analyzed from the front. With increasing age and concomitant drooping of the upper lip, an unaesthetic anterior tooth display may worsen. In most orthodontic patients, except those with marked "gummy" smiles, active intrusion of the maxillary incisors is undesirable. The best treatment strategy in the majority of deep overbite cases is to actively intrude the mandibular incisors, using double tubes on the mandibular first molars and continuous or segmented base arches or utility arches
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Another common mistake in orthodontic finishing is to create a straight (or even reverse) maxillary incisal curve relative to the smile line Parallelism of the incisal curve and the inner contour of the lower lip in smiling should be produced . this appearance can be achieved if the maxillary central incisors are symmetrically positioned .5-1mm longer than the lateral incisors If the lower lip shows a marked curvature in smiling, the distoincisal edges of the maxillary central incisors can be ground slightly without affecting functional occlusion
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Clinical Implications for High Smile Types Treatment alternatives include various combinations of orthodontic, periodontal, and surgical therapy. Intrusion base arches or utility arches may succeed in reducing a gummy smile orthodontically in some cases Such treatment can produce a remarkable change in facial appearance. A different treatment philosophy is needed for patients with high lip lines than for those with average or low smile types. Active maxillary incisor intrusion should be the goal in this category of patients.
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CONCLUSION: It is a significant error to attempt to put everyone into the same esthetic framework and an even greater error to try to do this from hard tissue relationships alone, taking it for granted that the soft tissues will follow along in a predictable fashion.
(1) esthetic considerations are paramount in planning appropriate orthodontic and orthognathic treatment, (2) rigid rules cannot be applied to this process.
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general guidelines for how to optimize dentofacial esthetics while satisfying other treatment goals.
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Dental and facial esthetic relationships must be evaluated in 3 dimensions, both dynamically and statically Two-dimensional hard tissue measurements as seen on sagittal or frontal radiographs are an imperfect reflection of what exists clinically. Treatment designed around the profile simply ignores the way that others see our patients and how our patients see themselves. The three quarter view of the face often reveals dentofacial characteristics, which although not measurable, yield valuable information in both diagnosis and treatment planning. Facial symmetry and vertical canting of the occlusal plane are important. It is not enough to just correct the teeth.
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The upper incisors are the key to esthetic orthodontic treatment planning. They must be positioned advantageously relative to the adjacent soft tissues both anteroposteriorly and vertically. The relative prominence of the nose and chin in relationship to the lips and overall facial contours is important Anterior tooth display, as observed in frontal and three-quarter views of the face, is more important than tooth prominence in profile views
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Extending the soft tissue envelope by expanding dental arches to increase hard tissue support for the lips and cheeks or enlarging the facial skeleton surgically to increase hard tissue support, usually is more esthetic than the reverse, especially when the effects of aging are considered. Greater soft tissue fullness gives a more youthful appearance. This is not an argument for routine expansion of severely crowded arches,
When possible, computer imaging should be utilized to simulate the soft tissue facial outcome that would most likely result from the proposed hard tissue changes. This allows for the patient’s input in the decision-making process.
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In summary, the 3 basic requirements for assessing dentofacial esthetics in orthodontics are: 1.
A dynamic and static 3-dimensional evaluation of the face derived primarily from the clinical examination of the patient.
2. A determination of lip-tooth relationships and anterior tooth display at rest and during facial animation. 3. An analysis of the dental and skeletal volume of the face as it effects the soft tissue facial mask.
When possible this should be an interactive process with the patient and is best facilitated through the use of graphic images via computer simulation. www.indiandentalacademy.com
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